JPS6458403A - Chuck - Google Patents

Abstract

PURPOSE:To prevent the generation of chucking trouble even if a stop trouble is generated on a movable body by keeping a holding hook in an opened state until the movable body is allowed to reach an advance edge by the advance of a plunger and permitting the holding hook to be opened and closed only at the advance edge. CONSTITUTION:Even if a trouble which suspends the advance transfer of a movable body 7 generates during said transfer, the relative shift between a hook transfer body 45 and a plunger 39 is suppressed by the rigid engagement between the upper surface 45b in the rear edge part of the hook transfer body 45 and a closing regulating surface 51a, and the hook transfer body 45 and the plunger 39 keep an integral form, and the closing of a holding hook 47 except at an advance edge position is prevented. When the slip preventing ring 9 of the movable body 7 contacts a stepped part 3a, the movable body 7 is stopped at the advance edge, and the engagement between the upper surface 45b in the rear edge part and the regulating surface 51a is released. Then, the plunger 39 advances furthermore, and the flat surface guiding part 49a of a pin 49 is guided by the inclined surface 37 to a floating plunger 33, and shifts the rear part 45a of the hook transfer body outwardly in the radial direction, and the holding hook 47 is shifted to the center side, keeping a supporting shaft 43 as center, and the edge part of a work W is held.